LEEDS, England (AP) - The bomber responsible for last week's explosion on a London double-decker bus was believed to be among the 13 people killed on board, a discovery that led to raids Tuesday on buildings in Leeds, a northern city with a strong Muslim community, news reports said.

In a key development in the investigation into the terror attacks that killed at least 52 people, British soldiers blasted their way into a modest Leeds row house Tuesday to search for explosives. Streets were cordoned off and about 500 people were evacuated, police said. Hours earlier, police searched five residences elsewhere in the city.

Some had speculated before (scroll down) that the attacks were suicide in nature, but that was in relation to the train bombs. Apparently, cell phones don't work in the London Underground so some believe that anyone detonating the bombs underground would have to be on-scene.

In relation to this bomb on the bus, its also been speculated that the bomb was not intended to go off on the bus. Some have said that it was meant for another target but was, for whatever reason, detonated early. I don't know what the basis of that is, but I've heard the rumor.

So, really, I don't know how much more this reveals. There are still a lot of questions that need answered before we can draw any real conclusions.

The cell phone issue is being misunderstood. No, cell phones usually can't receive calls in tunnels. That doesn't matter. In a situation like this, cell phones are just cheap, perfectly synchronized alarm clocks. The clocks on cell phones keep working even if they're off the network. Shutting off the cell phone network in tunnels would do nothing to prevent a cell phone detonator which used the phone's alarm clock. The alarm clock trigger also prevents authorities from tracing any call which would have triggered the bombs.

In Iraq and Israel, cell phone IEDs are often detonated by calling them. This allows the attackers to trigger the explosions when their target approaches the IED. Since cities are basically inifintely target-rich, there would be no need to call and trigger a bomb.

If the bombs all turn out to have been suicide triggered, this is a moot point.